Furnace lining



June 19, 1934. R. P. THOMPSON FURNACE LINING Filed Jan. 29, 1932 INI/ENTOR. 'F/obertPf'Thompson BY Q m A TTORNEY Patented June 19, 1934 f fr 1,963,157 'FURNACE LING.

Robert P. Thompson, Piermont, N. Y., assignor to The Superheater Company, New York, N. Y.

Application January 29, 1932, Serial No. 589,624

6 Claims.

My invention relates to water cooled walls for furnaces.

Furnaces lined with water tubes have been known for a great while. It has been proposed,

moreover, to increase the amount of heat transfer to given Water tubes in such locations by casting iron blocks directly on to the sides of the tubes which are to face the furnace, such blocks having widths on their furnace side greater than the diameters of the tubes so that each tube receives the radiant heat striking a greater area of the furnace wall than would be the case if the blocks were omitted. However, the cast on blocks have caused diiiiculty by cracking and breaking o.

It is an object of the present invention to provide novel arrangements whereby such diculties may be minimized.

In order that my invention, together with its lobjects and advantages may be clearly understood, I will now give, by way of example and in connection with the accompanying drawing, a detailed description of portions of furnace walls and blocks for use in such walls in accordance with my invention. In the drawing Fig. 1 is a horizontal sectional view thru a water tube forming part of the wall of a furnace and having secured thereto a protecting heat absorbing block within my invention.

Fig. 2 is a view similar to Fig. 1, but illustrating another form of protective heat absorbing block also within my invention.

Fig. 3 is an elevation of the tube and block appearing in Fig. 2.

Fig. 4 is a detail of a steel member of the kind used in building up a frame work to be used in the blocks such as shown in Figs. l, 2 and 3.

Fig. 5 is a plan view of the major portion of a frame work of the kind used in Figs. 1, 2 and 3.

In the drawing, 10 is a vertical water tube forming part of a wall of a furnace. Fixed to the furnace side of the tube 10 is a composite block 12 having a frame work 14, shown in detail in Fig. 5. Frame work 14 includes an arcuate face plate 16, the concave side of which is adapted to nt the outer face of the tube 10. Plate 16 is of weldable metal, preferably steel. Fixed to the convex or front face of plate 16 are several bridge pieces 18, 18, one of which is illustrated in detail in Fig. 4. Pieces 18 comprise each a longitudinal body from one side of which projects several fingers 20, 20 which lie parallel to each other and at substantially right angles to the body. The bridge members 18 are assembled on the plate 16 so that the ends of their fingers 20 lie in Contact with the convex face of plate 16. As shown, members 18 are arranged so that they will lie parallel to the axis of tube 10 when the frame work is placed on the tube. However, I do not limit myself to this. The fingers 20 have sufcient length so that recesses 22, 22 are formed between the bodies of the bridge pieces 18 and the face of plate 16 when the parts are assembled, such recesses being filled with cast metal in the completed block. The parts 16 and 18 are formed of weldable metal, preferably steel, so that bridge pieces 18 can be readily secured to the plate 16 by welding, bodies 24, 24 of weld metal being shown for securing the bridge pieces to the plate.

When the frame 14 has been made up as appears in Fig. 5, it is placed in a mold and a body of iron 25 is cast against the convex face of plate 16. The iron 25 ows into the recess 22 from both sides so that, when the parts have cooled, the cast iron is securely keyed to the frame work 14 not only by such welding as occurs between the parts at their surfaces, but also by interlocking engagement between the body 25 and the bridge pieces 18. 'I'he composite block 12 formed in the manner above described is then secured to the furnace side of a tube such as 10, preferably by bodies 26, 26 of weld metal along the edges of the plate 16.

The tube 10 illustrated in Figs. 2 and 3 is of the same character as that illustrated in Fig. 1 and, in fact, may be a portion of the same tube. In Figs. 2 and 3, however, the composite block 12a shown comprises a cast iron body portion 25a and also is fixed to the furnace face of the tube l0 by weld metal 26. Block 12a has a series of grooves 30, 30 in its furnace face. Grooves 30 run parallel to the axis of tube 10. I have found such grooves to materially lessen the stresses produced in blocks of cast iron such as 26a by changes in temperature. Such grooves, therefore, are useful not only in composite blocks of the type illustrated herein, but areuseful also in structures having the cast iron directly in contact with the face of the tubes, acting to materially reduce the cracking and breaking off of the iron from the tubes. I therefore do not limit myself to the use of grooves such as 30 in composite blocks, but consider their use in directly cast on furnace surfaces as within my claims.

What I claim is:

1. The combination of a heat absorbing tube, a cast metal body having a heat absorbing surface, a curved plate of metal, means including recessed pieces for fixing said plate to the side of said body opposite its heat absorbing surface, and means for holding said plate on said tube in heat transferring contact therewith.

2. The combination as set forth in claim 1 and in which bodies of weld metal secure the recessed pieces to the curved plate and the plate to the tube.

3. The combination of a curved metal base plate, of metal pieces xed thereto and having recesses therein, and a body of cast metal having heat transferring relation with said plate and interlocked with said pieces.

4. The combination as set forth in claim 3 together with a heat absorbing tube in contact with the curved plate, and means securing said tube to the plate.

5. As an article of manufacture, an arcuate base plate of heat conducting metal, a plurality of recessed frame members fixed to said plate on its convex side and projecting outwardly therefrom, and a body of cast metal in heat conducting relation tov said plate and projecting into the recesses of said frame pieces sogas to be interlocked therewith.

6. In a method of making heat absorbing furnace walls, the steps comprising xing recessed members to a plate, casting a body of metal against said plate so as to interlock With such members, and fastening said plate to a fluid cooled tube.

ROBERT P. THOMPSON. 

